MIT Technology Review - organ transplantshttp://www.technologyreview.com/tagged/organ-transplants/
enResearchers Create a Pituitary Gland from Scratchhttp://www.technologyreview.com/news/426082/researchers-create-a-pituitary-gland-from-scratch/
<p>The results could be an initial step toward generating viable, transplantable human organs.</p><p>Last spring, a research team at Japan’s RIKEN Center for Developmental Biology <a href="http://www.technologyreview.com/biomedicine/37294/">created retina-like structures</a> from cultured mouse embryonic stem cells. This week, the same group reports that it’s achieved an even more complicated feat—synthesizing a stem-cell-derived pituitary gland.</p>Wed, 09 Nov 2011 19:27:00 +0000digitalservices426082 at http://www.technologyreview.comA Genetic Test for Organ Rejectionhttp://www.technologyreview.com/news/423450/a-genetic-test-for-organ-rejection/
<p>Rising levels of donor DNA in recipients’ blood could mean the organ is in danger.</p><p>A new test could provide a noninvasive way of monitoring heart transplant patients for organ rejection. The test, which relies on DNA sequencing to detect fragments of the donor’s DNA in the recipient’s blood, still needs to be validated in clinical trials. But physicians hope it will ultimately offer an easy way to detect the signs of organ rejection in all types of transplant patients, perhaps earlier than other approaches.</p>Tue, 29 Mar 2011 04:00:00 +0000digitalservices423450 at http://www.technologyreview.comOld Livers Made New Againhttp://www.technologyreview.com/news/419358/old-livers-made-new-again/
<p>Unhealthy organs provide a framework for growing replacement ones.</p><p>Scientists at Massachusetts General Hospital in Boston have taken the first steps toward building functional, transplantable livers. In a study in rats, published online today by <em><a href="http://www.nature.com/nm/index.html" target="_blank">Nature Medicine</a></em>, the researchers took donor livers, gently stripped them of their cells while leaving other material intact, and then used the remaining structure as a scaffold on which to grow healthy liver cells. The result was a nearly complete organ that was transplanted into the rats and remained functional for up to eight hours.</p>Mon, 14 Jun 2010 04:00:00 +0000digitalservices419358 at http://www.technologyreview.comExtending the Life of Donated Organshttp://www.technologyreview.com/news/418765/extending-the-life-of-donated-organs/
<p>An experimental solution could buy time for transplant patients.</p><p>The 100,000-plus U.S. patients waiting for organ transplants face a perilous race against time. Most organs can only be preserved outside the body for somewhere between four and 24 hours–a problem that aggravates the chronic shortage of donors. In 2008, 6,684 patients died waiting for organs, according to the <a href="http://www.kidney.org/news/newsroom/fs_new/25factsorgdon&amp;trans.cfm" target="_blank">National Kidney Foundation</a>.</p>Mon, 03 May 2010 04:00:00 +0000digitalservices418765 at http://www.technologyreview.comPig-to-Monkey Transplant Treats Diabeteshttp://www.technologyreview.com/news/413437/pig-to-monkey-transplant-treats-diabetes/
<p>Embryonic tissue could let xenotransplants evade the host’s immune system.</p><p>Using embryonic tissue for interspecies organ transplants offers a way to evade the host’s immune system, say scientists who used the method to treat type 1 diabetes in primates. By transplanting embryonic pancreatic tissue from pigs to monkeys, Israeli researchers report that they were able to reverse the primates’ insulin deficiency.<br /><br /> The key, the researchers say, is the embryonic tissue’s ability to grow into a new pancreas that uses blood vessels from the host animal. The host blood vessels are not subject to the dangerous immune reaction that has always dogged xenotransplants of mature pancreatic material.<br /><br /> The research team, led by <a href="http://www.weizmann.ac.il/immunology/ReisnerPage.html" target="_blank">Yair Reisner</a> of the Weizmann Institute, claims that the results, published in the latest issue of the journal <a href="http://www.pnas.org" target="_blank"><em>PNAS</em></a>, could offer an attractive replacement therapy for type 1 diabetes, an autoimmune disease in which the destruction of the pancreas means that sufferers rely on injections of the hormone insulin to control their blood-sugar levels.<br /><br /> In an earlier study, the researchers found evidence that semiformed pancreatic tissue taken from pig embryos at 42 days of gestation appeared to offer the best combination of characteristics for xenotransplantation. According to Reisner, if they’re harvested too early, there may not be enough partially differentiated pancreatic cells. But if taken too late, the tissues’ ability to grow into a new organ is diminished, perhaps because they contain too few stem cells, while their ability to cause immune rejection increases.<br /><br /> In the latest study, the researchers transplanted 42-day-old pig pancreatic tissue into monkeys with induced type 1 diabetes. The first pair of animals involved in the study died soon after transplantation from an infection caused by too much immunosuppressive therapy.<br /><br /> The second pair of animals received milder immunotherapy and survived for a year. Furthermore, within five months of treatment, the animals had grown new pancreases and were no longer reliant on insulin injections. This indicates that the replacement organs had sufficient islets–tiny, insulin-producing structures consisting of around 1,500 beta cells, which have their own intricate vascular systems.<br /><br /> Radioimmunoassay tests confirmed that the insulin produced by the monkey was porcine, while the network of vessels running through the new organ was made of host cells. “This is important because it meant the monkey’s immune system did not attack the vessels,” says Reisner.<br /> This type of immune reaction has been a bugbear for researchers, he says, because primates, including humans, produce a class of antibodies that attack the sugar molecules that coat pig blood-vessel tissue.</p>Tue, 12 May 2009 04:00:00 +0000digitalservices413437 at http://www.technologyreview.com